From df1c1afdafcf8c9c46b18f274fc7f01f13ff05da Mon Sep 17 00:00:00 2001
From: Michael Goulet <michael@errs.io>
Date: Wed, 31 May 2023 17:45:45 +0000
Subject: [PATCH] Check that RPITs are compatible with the opaques inferred
during HIR typeck too
---
.../src/collect/type_of/opaque.rs | 65 +++++++++--------
.../rustc_middle/src/ty/typeck_results.rs | 4 --
tests/ui/chalkify/bugs/async.stderr | 13 +---
tests/ui/dyn-star/param-env-infer.next.stderr | 35 ----------
tests/ui/impl-trait/auto-trait-leak.stderr | 70 -------------------
.../multiple-defining-usages-in-body.rs | 2 +-
.../multiple-defining-usages-in-body.stderr | 12 ++--
7 files changed, 46 insertions(+), 155 deletions(-)
diff --git a/compiler/rustc_hir_analysis/src/collect/type_of/opaque.rs b/compiler/rustc_hir_analysis/src/collect/type_of/opaque.rs
index da82ce1d523..4d96a7ff4c3 100644
--- a/compiler/rustc_hir_analysis/src/collect/type_of/opaque.rs
+++ b/compiler/rustc_hir_analysis/src/collect/type_of/opaque.rs
@@ -1,3 +1,4 @@
+use rustc_errors::StashKey;
use rustc_hir::def_id::LocalDefId;
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::{self as hir, Expr, ImplItem, Item, Node, TraitItem};
@@ -210,12 +211,40 @@ pub(super) fn find_opaque_ty_constraints_for_rpit<'tcx>(
def_id: LocalDefId,
owner_def_id: LocalDefId,
) -> Ty<'_> {
- let concrete = tcx.mir_borrowck(owner_def_id).concrete_opaque_types.get(&def_id).copied();
+ let tables = tcx.typeck(owner_def_id);
- if let Some(concrete) = concrete {
+ // Check that all of the opaques we inferred during HIR are compatible.
+ // FIXME: We explicitly don't check that the types inferred during HIR
+ // typeck are compatible with the one that we infer during borrowck,
+ // because that one actually sometimes has consts evaluated eagerly so
+ // using strict type equality will fail.
+ let mut hir_opaque_ty: Option<ty::OpaqueHiddenType<'tcx>> = None;
+ if tables.tainted_by_errors.is_none() {
+ for (&opaque_type_key, &hidden_type) in &tables.concrete_opaque_types {
+ if opaque_type_key.def_id != def_id {
+ continue;
+ }
+ let concrete_type = tcx.erase_regions(
+ hidden_type.remap_generic_params_to_declaration_params(opaque_type_key, tcx, true),
+ );
+ if let Some(prev) = &mut hir_opaque_ty {
+ if concrete_type.ty != prev.ty && !(concrete_type, prev.ty).references_error() {
+ prev.report_mismatch(&concrete_type, def_id, tcx).stash(
+ tcx.def_span(opaque_type_key.def_id),
+ StashKey::OpaqueHiddenTypeMismatch,
+ );
+ }
+ } else {
+ hir_opaque_ty = Some(concrete_type);
+ }
+ }
+ }
+
+ let mir_opaque_ty = tcx.mir_borrowck(owner_def_id).concrete_opaque_types.get(&def_id).copied();
+ if let Some(mir_opaque_ty) = mir_opaque_ty {
let scope = tcx.hir().local_def_id_to_hir_id(owner_def_id);
debug!(?scope);
- let mut locator = RpitConstraintChecker { def_id, tcx, found: concrete };
+ let mut locator = RpitConstraintChecker { def_id, tcx, found: mir_opaque_ty };
match tcx.hir().get(scope) {
Node::Item(it) => intravisit::walk_item(&mut locator, it),
@@ -224,38 +253,16 @@ pub(super) fn find_opaque_ty_constraints_for_rpit<'tcx>(
other => bug!("{:?} is not a valid scope for an opaque type item", other),
}
- concrete.ty
+ mir_opaque_ty.ty
} else {
- let tables = tcx.typeck(owner_def_id);
if let Some(guar) = tables.tainted_by_errors {
- // Some error in the
- // owner fn prevented us from populating
+ // Some error in the owner fn prevented us from populating
// the `concrete_opaque_types` table.
tcx.ty_error(guar)
} else {
// Fall back to the RPIT we inferred during HIR typeck
- let mut opaque_ty: Option<ty::OpaqueHiddenType<'tcx>> = None;
- for (&opaque_type_key, &hidden_type) in &tables.concrete_opaque_types {
- if opaque_type_key.def_id != def_id {
- continue;
- }
- let concrete_type =
- tcx.erase_regions(hidden_type.remap_generic_params_to_declaration_params(
- opaque_type_key,
- tcx,
- true,
- ));
- if let Some(prev) = &mut opaque_ty {
- if concrete_type.ty != prev.ty && !(concrete_type, prev.ty).references_error() {
- prev.report_mismatch(&concrete_type, def_id, tcx).emit();
- }
- } else {
- opaque_ty = Some(concrete_type);
- }
- }
-
- if let Some(opaque_ty) = opaque_ty {
- opaque_ty.ty
+ if let Some(hir_opaque_ty) = hir_opaque_ty {
+ hir_opaque_ty.ty
} else {
// We failed to resolve the opaque type or it
// resolves to itself. We interpret this as the
diff --git a/compiler/rustc_middle/src/ty/typeck_results.rs b/compiler/rustc_middle/src/ty/typeck_results.rs
index 68bae5828c5..8cbffa14850 100644
--- a/compiler/rustc_middle/src/ty/typeck_results.rs
+++ b/compiler/rustc_middle/src/ty/typeck_results.rs
@@ -155,10 +155,6 @@ pub struct TypeckResults<'tcx> {
/// We also store the type here, so that the compiler can use it as a hint
/// for figuring out hidden types, even if they are only set in dead code
/// (which doesn't show up in MIR).
- ///
- /// These types are mapped back to the opaque's identity substitutions
- /// (with erased regions), which is why we don't associated substs with any
- /// of these usages.
pub concrete_opaque_types: FxIndexMap<ty::OpaqueTypeKey<'tcx>, ty::OpaqueHiddenType<'tcx>>,
/// Tracks the minimum captures required for a closure;
diff --git a/tests/ui/chalkify/bugs/async.stderr b/tests/ui/chalkify/bugs/async.stderr
index 7e64e67f24c..e6d46b02706 100644
--- a/tests/ui/chalkify/bugs/async.stderr
+++ b/tests/ui/chalkify/bugs/async.stderr
@@ -13,16 +13,9 @@ error: internal compiler error: projection clauses should be implied from elsewh
LL | async fn foo(x: u32) -> u32 {
| ^^^query stack during panic:
#0 [typeck] type-checking `foo`
-#1 [thir_body] building THIR for `foo`
-#2 [check_match] match-checking `foo`
-#3 [mir_built] building MIR for `foo`
-#4 [unsafety_check_result] unsafety-checking `foo`
-#5 [mir_const] preparing `foo` for borrow checking
-#6 [mir_promoted] promoting constants in MIR for `foo`
-#7 [mir_borrowck] borrow-checking `foo`
-#8 [type_of] computing type of `foo::{opaque#0}`
-#9 [check_mod_item_types] checking item types in top-level module
-#10 [analysis] running analysis passes on this crate
+#1 [type_of] computing type of `foo::{opaque#0}`
+#2 [check_mod_item_types] checking item types in top-level module
+#3 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 2 previous errors
diff --git a/tests/ui/dyn-star/param-env-infer.next.stderr b/tests/ui/dyn-star/param-env-infer.next.stderr
index 64d76bb04b1..408abecc30d 100644
--- a/tests/ui/dyn-star/param-env-infer.next.stderr
+++ b/tests/ui/dyn-star/param-env-infer.next.stderr
@@ -13,41 +13,6 @@ error[E0391]: cycle detected when computing type of `make_dyn_star::{opaque#0}`
LL | fn make_dyn_star<'a, T: PointerLike + Debug + 'a>(t: T) -> impl PointerLike + Debug + 'a {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
-note: ...which requires borrow-checking `make_dyn_star`...
- --> $DIR/param-env-infer.rs:11:1
- |
-LL | fn make_dyn_star<'a, T: PointerLike + Debug + 'a>(t: T) -> impl PointerLike + Debug + 'a {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires promoting constants in MIR for `make_dyn_star`...
- --> $DIR/param-env-infer.rs:11:1
- |
-LL | fn make_dyn_star<'a, T: PointerLike + Debug + 'a>(t: T) -> impl PointerLike + Debug + 'a {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires preparing `make_dyn_star` for borrow checking...
- --> $DIR/param-env-infer.rs:11:1
- |
-LL | fn make_dyn_star<'a, T: PointerLike + Debug + 'a>(t: T) -> impl PointerLike + Debug + 'a {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires unsafety-checking `make_dyn_star`...
- --> $DIR/param-env-infer.rs:11:1
- |
-LL | fn make_dyn_star<'a, T: PointerLike + Debug + 'a>(t: T) -> impl PointerLike + Debug + 'a {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires building MIR for `make_dyn_star`...
- --> $DIR/param-env-infer.rs:11:1
- |
-LL | fn make_dyn_star<'a, T: PointerLike + Debug + 'a>(t: T) -> impl PointerLike + Debug + 'a {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires match-checking `make_dyn_star`...
- --> $DIR/param-env-infer.rs:11:1
- |
-LL | fn make_dyn_star<'a, T: PointerLike + Debug + 'a>(t: T) -> impl PointerLike + Debug + 'a {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires building THIR for `make_dyn_star`...
- --> $DIR/param-env-infer.rs:11:1
- |
-LL | fn make_dyn_star<'a, T: PointerLike + Debug + 'a>(t: T) -> impl PointerLike + Debug + 'a {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: ...which requires type-checking `make_dyn_star`...
--> $DIR/param-env-infer.rs:11:1
|
diff --git a/tests/ui/impl-trait/auto-trait-leak.stderr b/tests/ui/impl-trait/auto-trait-leak.stderr
index aa4ee75bb75..c0c4cd5013e 100644
--- a/tests/ui/impl-trait/auto-trait-leak.stderr
+++ b/tests/ui/impl-trait/auto-trait-leak.stderr
@@ -4,41 +4,6 @@ error[E0391]: cycle detected when computing type of `cycle1::{opaque#0}`
LL | fn cycle1() -> impl Clone {
| ^^^^^^^^^^
|
-note: ...which requires borrow-checking `cycle1`...
- --> $DIR/auto-trait-leak.rs:12:1
- |
-LL | fn cycle1() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires promoting constants in MIR for `cycle1`...
- --> $DIR/auto-trait-leak.rs:12:1
- |
-LL | fn cycle1() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires preparing `cycle1` for borrow checking...
- --> $DIR/auto-trait-leak.rs:12:1
- |
-LL | fn cycle1() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires unsafety-checking `cycle1`...
- --> $DIR/auto-trait-leak.rs:12:1
- |
-LL | fn cycle1() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires building MIR for `cycle1`...
- --> $DIR/auto-trait-leak.rs:12:1
- |
-LL | fn cycle1() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires match-checking `cycle1`...
- --> $DIR/auto-trait-leak.rs:12:1
- |
-LL | fn cycle1() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires building THIR for `cycle1`...
- --> $DIR/auto-trait-leak.rs:12:1
- |
-LL | fn cycle1() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
note: ...which requires type-checking `cycle1`...
--> $DIR/auto-trait-leak.rs:14:5
|
@@ -50,41 +15,6 @@ note: ...which requires computing type of `cycle2::{opaque#0}`...
|
LL | fn cycle2() -> impl Clone {
| ^^^^^^^^^^
-note: ...which requires borrow-checking `cycle2`...
- --> $DIR/auto-trait-leak.rs:19:1
- |
-LL | fn cycle2() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires promoting constants in MIR for `cycle2`...
- --> $DIR/auto-trait-leak.rs:19:1
- |
-LL | fn cycle2() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires preparing `cycle2` for borrow checking...
- --> $DIR/auto-trait-leak.rs:19:1
- |
-LL | fn cycle2() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires unsafety-checking `cycle2`...
- --> $DIR/auto-trait-leak.rs:19:1
- |
-LL | fn cycle2() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires building MIR for `cycle2`...
- --> $DIR/auto-trait-leak.rs:19:1
- |
-LL | fn cycle2() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires match-checking `cycle2`...
- --> $DIR/auto-trait-leak.rs:19:1
- |
-LL | fn cycle2() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires building THIR for `cycle2`...
- --> $DIR/auto-trait-leak.rs:19:1
- |
-LL | fn cycle2() -> impl Clone {
- | ^^^^^^^^^^^^^^^^^^^^^^^^^
note: ...which requires type-checking `cycle2`...
--> $DIR/auto-trait-leak.rs:20:5
|
diff --git a/tests/ui/impl-trait/multiple-defining-usages-in-body.rs b/tests/ui/impl-trait/multiple-defining-usages-in-body.rs
index c3a6f09f86d..86661153a0d 100644
--- a/tests/ui/impl-trait/multiple-defining-usages-in-body.rs
+++ b/tests/ui/impl-trait/multiple-defining-usages-in-body.rs
@@ -4,9 +4,9 @@ impl Trait for () {}
fn foo<T: Trait, U: Trait>() -> impl Trait {
//~^ WARN function cannot return without recursing [unconditional_recursion]
let a: T = foo::<T, U>();
- //~^ ERROR concrete type differs from previous defining opaque type use
loop {}
let _: T = foo::<U, T>();
+ //~^ ERROR concrete type differs from previous defining opaque type use
}
fn main() {}
diff --git a/tests/ui/impl-trait/multiple-defining-usages-in-body.stderr b/tests/ui/impl-trait/multiple-defining-usages-in-body.stderr
index 06991749bfa..f3c090408b4 100644
--- a/tests/ui/impl-trait/multiple-defining-usages-in-body.stderr
+++ b/tests/ui/impl-trait/multiple-defining-usages-in-body.stderr
@@ -11,15 +11,15 @@ LL | let a: T = foo::<T, U>();
= note: `#[warn(unconditional_recursion)]` on by default
error: concrete type differs from previous defining opaque type use
+ --> $DIR/multiple-defining-usages-in-body.rs:8:16
+ |
+LL | let _: T = foo::<U, T>();
+ | ^^^^^^^^^^^^^ expected `T`, got `U`
+ |
+note: previous use here
--> $DIR/multiple-defining-usages-in-body.rs:6:16
|
LL | let a: T = foo::<T, U>();
- | ^^^^^^^^^^^^^ expected `U`, got `T`
- |
-note: previous use here
- --> $DIR/multiple-defining-usages-in-body.rs:9:16
- |
-LL | let _: T = foo::<U, T>();
| ^^^^^^^^^^^^^
error: aborting due to previous error; 1 warning emitted